/*
 * Copyright (c) 2007, 2015, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * Copyright 2001-2004 The Apache Software Foundation.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
/*
 * $Id: LiteralAttribute.java,v 1.2.4.1 2005/09/12 10:38:03 pvedula Exp $
 */

package com.sun.org.apache.xalan.internal.xsltc.compiler;

import com.sun.org.apache.bcel.internal.generic.ConstantPoolGen;
import com.sun.org.apache.bcel.internal.generic.InstructionList;
import com.sun.org.apache.bcel.internal.generic.PUSH;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ClassGenerator;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.MethodGenerator;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.TypeCheckError;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Util;

import com.sun.org.apache.xml.internal.serializer.ElemDesc;
import com.sun.org.apache.xml.internal.serializer.SerializationHandler;

/**
 * @author Jacek Ambroziak
 * @author Santiago Pericas-Geertsen
 * @author Morten Jorgensen
 */
final class LiteralAttribute extends Instruction {

  private final String _name;         // Attribute name (incl. prefix)
  private final AttributeValue _value; // Attribute value

  /**
   * Creates a new literal attribute (but does not insert it into the AST).
   *
   * @param name the attribute name (incl. prefix) as a String.
   * @param value the attribute value.
   * @param parser the XSLT parser (wraps XPath parser).
   */
  public LiteralAttribute(String name, String value, Parser parser,
      SyntaxTreeNode parent) {
    _name = name;
    setParent(parent);
    _value = AttributeValue.create(this, value, parser);
  }

  public void display(int indent) {
    indent(indent);
    Util.println("LiteralAttribute name=" + _name + " value=" + _value);
  }

  public Type typeCheck(SymbolTable stable) throws TypeCheckError {
    _value.typeCheck(stable);
    typeCheckContents(stable);
    return Type.Void;
  }

  protected boolean contextDependent() {
    return _value.contextDependent();
  }

  public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
    final ConstantPoolGen cpg = classGen.getConstantPool();
    final InstructionList il = methodGen.getInstructionList();

    // push handler
    il.append(methodGen.loadHandler());
    // push attribute name - namespace prefix set by parent node
    il.append(new PUSH(cpg, _name));
    // push attribute value
    _value.translate(classGen, methodGen);

    // Generate code that calls SerializationHandler.addUniqueAttribute()
    // if all attributes are unique.
    SyntaxTreeNode parent = getParent();
    if (parent instanceof LiteralElement
        && ((LiteralElement) parent).allAttributesUnique()) {

      int flags = 0;
      boolean isHTMLAttrEmpty = false;
      ElemDesc elemDesc = ((LiteralElement) parent).getElemDesc();

      // Set the HTML flags
      if (elemDesc != null) {
        if (elemDesc.isAttrFlagSet(_name, ElemDesc.ATTREMPTY)) {
          flags = flags | SerializationHandler.HTML_ATTREMPTY;
          isHTMLAttrEmpty = true;
        } else if (elemDesc.isAttrFlagSet(_name, ElemDesc.ATTRURL)) {
          flags = flags | SerializationHandler.HTML_ATTRURL;
        }
      }

      if (_value instanceof SimpleAttributeValue) {
        String attrValue = ((SimpleAttributeValue) _value).toString();

        if (!hasBadChars(attrValue) && !isHTMLAttrEmpty) {
          flags = flags | SerializationHandler.NO_BAD_CHARS;
        }
      }

      il.append(new PUSH(cpg, flags));
      il.append(methodGen.uniqueAttribute());
    } else {
      // call attribute
      il.append(methodGen.attribute());
    }
  }

  /**
   * Return true if at least one character in the String is considered to
   * be a "bad" character. A bad character is one whose code is:
   * less than 32 (a space),
   * or greater than 126,
   * or it is one of '<', '>', '&' or '\"'.
   * This helps the serializer to decide whether the String needs to be escaped.
   */
  private boolean hasBadChars(String value) {
    char[] chars = value.toCharArray();
    int size = chars.length;
    for (int i = 0; i < size; i++) {
      char ch = chars[i];
      if (ch < 32 || 126 < ch || ch == '<' || ch == '>' || ch == '&' || ch == '\"') {
        return true;
      }
    }
    return false;
  }

  /**
   * Return the name of the attribute
   */
  public String getName() {
    return _name;
  }

  /**
   * Return the value of the attribute
   */
  public AttributeValue getValue() {
    return _value;
  }

}
